The postpubertal incidence of idiopathic varicocele is about 20%. Of the men attending an infertility service, 40-50% suffer from a varicocele. Varicocele, therefore, is one of the main causes of male sub- or infertility. In most cases, improvement of sperm concentration and conception rate could be observed after varicocele treatment. Consequently, varicocele treatment is indicated in men with pathological spermiograms and a desire to have children. The different concepts of treatment are discussed, distinguishing between operative and interdisciplinary therapy.